1. Field of the Invention
The present invention relates to volume adjusting apparatus, method and computer program product for inputting sounds from a plurality of inputting terminals to respectively set volume levels of the sounds thus inputted, and respectively outputting the sounds at the volume levels thus set, and more particularly to volume adjusting apparatus, method and computer program product for inputting sounds from a plurality of inputting terminals to respectively set volume levels of the sounds thus inputted at time intervals, and respectively outputting the sounds at the volume levels thus set at time intervals.
2. Description of the Related Art
Up until now, there have been proposed a wide variety of volume adjusting apparatus, each of which comprises a plurality of sound inputting terminals for respectively inputting sounds, a plurality of volume setting means respectively connected with the sound inputting terminals to respectively set volume levels of the sounds inputted by the sound inputting terminals, and a plurality of sound outputting terminals for respectively outputting the sounds at the volume levels respectively set by the volume setting means. Such volume adjusting apparatus can respectively input sounds from, for example, a plurality of sound sources, respectively set volume levels of sounds thus inputted and respectively output the sounds at the volume levels thus set to, for example, a plurality of speakers, not shown, placed in a theme park or in a place at the entertaining event. The volume adjusting apparatus of this type is gaining popularity more than before as a result of the increase in the number of the theme parks and entertaining events.
One typical example of the volume adjusting apparatus will be described hereinafter with reference to FIG. 14. The conventional volume adjusting apparatus 900 is shown in FIG. 14 as comprising: a plurality of sound inputting terminals 1—1 to 1-n for respectively inputting sound elements vin-1 to vin-n; a plurality of volume setting means 3-1 to 3-n respectively connected with the sound inputting terminals 1—1 to 1-n to respectively set volume levels of the sound elements vin-1 to vin-n inputted by the sound inputting terminals 1—1 to 1-n; and a plurality of sound outputting terminals 2-1 to 2-n for respectively outputting the sound elements vout-1 to vout-n at the volume levels respectively set by the volume setting means 3-1 to 3-n. The volume adjusting apparatus 900 further comprises: timer means 4 for outputting a trigger signal at a time interval; and a plurality of volume envelope generating means 5-1 to 5-n respectively corresponding to the volume setting means 3-1 to 3-n for selectively generating volume envelope values for respective volume setting means 3-1 to 3-n in accordance with predetermined envelope forms in response to the trigger signal outputted by the timer means 4 at the time interval. The volume setting means 3-1 to 3-n are operative to respectively set the volume levels of the sound elements vin-1 to vin-n inputted by the sound inputting terminals 1—1 to 1-n in accordance with the volume envelope values respectively generated by the volume envelope generating means 5-1 to 5-n in response to the trigger signal outputted by the timer means 4 at the time interval.
The conventional volume adjusting apparatus 900 thus constructed can control the volume levels of the inputted sound elements in accordance with the volume envelope values respectively generated by the volume envelope generating means 5-1 to 5-n in response to the trigger signal outputted by the timer means 4 at the time interval, thereby enabling to adjust and make sounds naturally audible by the human ear.
The conventional volume adjusting apparatus 900, however, encounters a problem that the conventional volume adjusting apparatus 900 cannot detect the state of each of the volume envelope generating means 5-1 to 5-n, i.e., whether any one of volume envelope values for the volume setting means 3-1 to 3-n respectively generated by the volume envelope generating means 5-1 to 5-n remains unchanged or not. This means that all of the volume envelope generating means 5-1 to 5-n are required to respectively set the volume setting means 3-1 to 3-n at a time interval indicated by the trigger signal outputted by the timer means 4 regardless whether any one of volume envelope values for the volume setting means 3-1 to 3-n respectively generated by the volume envelope generating means 5-1 to 5-n remains unchanged or not. This leads to the fact that the conventional volume adjusting apparatus 900 increases a time required to set the volume setting means 3-1 to 3-n as the number of the volume setting means 3-1 to 3-n increases, thereby aggravating the response time of the conventional volume adjusting apparatus 900. The response time of the conventional volume adjusting apparatus 900 may be further aggravated especially in the case that the volume setting means 3-1 to 3-n are manufactured as, for example, hardware units to be manually operated.
The conventional volume adjusting apparatus 900 encounters another problem that the volume setting means 3-1 to 3-n cannot respectively set the volume levels of the sound elements vin-1 to vin-n in accordance with the volume envelope values respectively generated by the volume envelope generating means 5-1 to 5-n at the time interval indicated by the timer means 4 if the response time is excessively aggravated as a result of the increase in the number of the volume setting means 3-1 to 3-n. 
The present invention contemplates resolution of such problems.